Outer lead bonding head and method of bonding outer lead

Abstract

A nozzle shaft is moved down, and a semiconductor chip sucked to the lower end of the nozzle shaft is placed on a circuit board. Then, a thermally press-bonding member is moved down, and the outer leads of the semiconductor chip are pressed to the circuit board by the thermally press-bonding member. Thereafter, the thermally press-bonded member is pressed by pressing means to strongly press the outer leads to the circuit board, the thermally press-bonding member is then raised to release the pressing state, and the outer leads are thermally press-bonded to the circuit board.

What is claimed is: 
     
       1. An outer lead bonding head comprising a vertically movable nozzle shaft having a suction unit to hold a semiconductor or chip semiconductor at a lower end thereof, a thermally press-bonding member provided independently of the suction unit at the side of the suction unit, heating means for heating the thermally press-bonding member, means to vertically move said thermally press-bonding member independent of said heating means and said suction unit for providing a space between said heating means and said thermal press-bonding member for control of heating said thermal press-bonding member and pressing means for pressing the thermally press-bonding member to outer leads of the semiconductor placed on a circuit board by said suction unit. 
     
     
       2. An outer lead bonding head according to claim 1, wherein said heating means has a heat transfer member for contacting said thermally press-bonding member to heat said thermally press-bonding member through the heat transfer member. 
     
     
       3. An outer lead bonding head comprising a nozzle shaft having a suction unit to hold a semiconductor or chip semiconductor at a lower end thereof, heating means, and a thermally press-bonding member separate from said heating means at the lower portion of said heating means and movable with respect to said heating means for control of heating of said thermal press-bonding member, said thermal press-bonding member for thermally press-bonding to the circuit board outer leads of the semiconductor or chip placed on a circuit board by said suction unit. 
     
     
       4. A method of bonding outer leads comprising the steps of moving down a nozzle shaft, placing a semiconductor chip suctioned to the lower end of said nozzle shaft on a circuit board, preheating a thermally press-bonding member, then moving down the thermally press-bonding member, pressing the outer leads of the semiconductor chip to the circuit board, using a weak force then further pressing the thermally press-bonding member using a stronger force to strongly press the outer leads to the circuit board, then moving up the thermally press-bonding member to release the pressing state, thereby providing thermally press-bonding of the outer leads to the circuit board. 
     
     
       5. An outer lead bonding head comprising a vertically movable nozzle shaft having a suction unit to hold a semiconductor or chip semiconductor at a lower end thereof, a thermally press-bonding member disposed at the side of said suction unit for thermally press-bonding outer leads placed on a circuit board by said suction unit to the circuit board, and cooling means for blowing chilled gas to the thermally press-bonding member. 
     
     
       6. An outer lead bonding head according to claim 5, wherein an erecting tube for containing said nozzle shaft and a pipe for feeding chilled gas to said erecting tube are provided, and chilled gas is blown from the lower end of said erecting tube downward. 
     
     
       7. A method of bonding outer leads, comprising the steps of moving down a nozzle shaft, placing the outer leads of a semiconductor chip suctioned to a suction portion at the lower end of said nozzle shaft onto electrodes of a circuit board, then moving down a thermally press-bonding member heated by a heating means, pressing said press-bonding member onto the outer leads, thereby to melt said electrodes, subsequently blowing a chilled gas to said press-bonding member to cool the press-bonding member and the electrodes, and raising the press-bonding member to release the pressure, thereby providing thermally press-bonding of the outer leads onto the electrodes formed on the circuit board.